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Economic dispatch has a significant effect on optimal economical operation in the power systems in industrial revolution 4.0 in terms of considerable savings in revenue. Various non-linearity are added to make the fossil fuel-based power systemsmore practical. In order to achieve an accurate economical schedule, valve point loading effect, ramp rate constraints, and prohibited operating zones are being considered for realistic scenarios. In this paper, an improved, and modified version of conventional particle swarm optimization (PSO), called Oscillatory PSO (OPSO), is devised to provide a cheaper schedule with optimum cost. The conventional PSO is improved by deriving a mechanism enabling the particle towards the trajectories of oscillatory motion to acquire the entire search space. A set of differential equations is implemented to expose the condition for trajectory motion in oscillation. Using adaptive inertia weights, this OPSO method provides an optimized cost of generation as compared to the conventional particle swarm optimization and other new meta-heuristic approaches. [ABSTRACT FROM AUTHOR]

This paper highlights the study and implementation of various types of Fuzzy structures using rule based interfaces for steady state and transient analysis with Hardware in Loop validation. A mathematical modeling of Type III DFIG based modified wind turbine is designed to develop maximum efficiency during faults. The modified wind turbine is controlled by various controller s illustrated in this chapter. The Mode 1 and Mode 2 are basic controllers rather the mode 3 and mode 4 are proposed controllers using derivative and integral control to active power with PI and Fuzzy logic to reactive power. This control enhance the transient stability of the wind d turbine system. The active and reactive power can be controlled and faster response can be achieved under fault conditions. All the mode results are discussed and a comparison with proposed technique is highlighted in this work. The model is designed using MATLAB simulink and the case studies are explained by taking different wind speeds and fault conditions. The model is validated using TYPHOON hardware in Loop Real Time software to get comparative results. [ABSTRACT FROM AUTHOR]

Although atomically precise polyhydrido copper nanoclusters are of prime interest for a variety of applications, they have so far remained scarce. Herein, this work describes the synthesis of a dithiophosphate‐protected copper(I) hydride‐rich nanocluster (NC), [Cu30H18{S2P(OnPr)2}12] (1H), fully characterized by various spectroscopic methods and single‐crystal X‐ray diffraction. The X‐ray structure of 1H reveals an unprecedented central Cu12 hollow icosahedron. Six faces of this icosahedron are capped by Cu3 triangles, the whole Cu30 core being wrapped by twelve dithiophosphate ligands and the whole cluster has ideal S6 symmetry. The locations of the 18 hydrides in 1H were ascertained by a single‐crystal neutron diffraction study. They are composed of three types: capping μ3‐H, interstitial μ4‐H (seesaw) and μ5‐H ligands (square pyramidal), in good agreement with the DFT simulations. The numbers of hydrides and ligand resonances in the 1H NMR spectrum of 1H are in line with their coordination environment in the solid state, retaining the S6 symmetry in solution. Furthermore, two new Se‐protected polyhydrido copper nanoclusters, [Cu30H18{Se2P(OR)2}12] (2H: R=iPr 3H: R=iBu) were synthesized from their sulfur relative 1H via ligand displacement reaction and their X‐ray structures feature the exceptional case where both the NC shape and size are fully conserved during the course of ligand exchange. DFT and TD‐DFT calculations allow understanding the bonding and optical properties of clusters 1H–3H. In addition, the reaction of 1H with [Pd(PPh3)2Cl2] in the presence of terminal alkynes led to the formation of new bimetallic Cu−Pd alloy clusters [PdCu14H2{S2P(OnPr)2}6(C≡CR)6] (4: R=Ph; 5: R=C6H4F). [ABSTRACT FROM AUTHOR]

When a Double Fed Induction Generator (DFIG) primarily based Type-III Wind Turbine (WT) is connected to the grid without a digital power interface, the terminal voltage or reactive electricity output can't be managed accordingly. Many techniques have been developed to overcome the issue of low voltage due to faults. This paper tries to define such active methods by presenting a complete analysis of LVRT strategies for DFIG-based Wind Energy Conversion Systems (WECS) in terms of overall adaptive performance, operation complexity of controllers, and cost-effectiveness. This paper aims to highlight the methods of increasing the ability of LVRT relying on the configuration of the relationship into 3 major areas according to its grid integrations. Shunt connections of FACTS devices are used in WECS to study their effectiveness and benefits. The system models are simulated in MATLAB/Simulink and the results are discussed. [ABSTRACT FROM AUTHOR]

Relaxation mechanism, conductivity and magnetoelectric properties of (Nd1/2Li1/2)(Fe2/3Mo1/3)O3 multiferroic have been investigated systematically. This material was synthesized by a solid-state reaction route. Thermogravimetric analysis is enforced to perceive the percentage of weight change with rise in temperature in order to obtain the calcination temperature of the material. The preliminary structural study using X-ray diffraction data reveals the orthorhombic structure of the material. The complex plot of impedance data helped to distinguish the involvement of grain as well as grain boundary effects towards the overall electrical properties of the compound. Temperature-dependent electrical conductivity plots exhibit the presence of thermally activated conduction mechanism of the compound. The magnetic field dependence of magnetization (M–H loop) showed the presence of ferromagnetic nature of the material. The value of magnetoelectric coupling coefficient of prepared material is found to be 2.7 mV Cm−1 Oe−1. [ABSTRACT FROM AUTHOR]

Shape-memory polymers (SMPs) are stimuli-responsive shape-varying polymers. Now a days they become a great interest for fundamental research and technological innovation. Here a brief review of the recent trends in the arena of SMPs is presented with particular focus on their structure, shape-memory effects and practical application. A special attention is given to smart multi-responsive and multi-functional advanced SMP materials as they are of emerging technological class. Important applications of SMP in the field of biomedical engineering, polymer domain, and material replacement are explained in the applications part. Traditional shape memory polymers (SMPs) are those which are capable of memorizing a temporary shape and recovering to the initial shape upon heating. Though SMP is old concept initiated half a century ago but its applications in variety of fields is the topic where it’s lagging. As such, the intent of the present paper isn’t to supply an intensive review of the SMP analysis. Instead, the main focus is on light samples of recently emerged from memory phenomena, their thoughtful impact to the sector of SMP on each scientific and sensible fronts, and future outlook. [ABSTRACT FROM AUTHOR]

In the present communication, studies of some physical properties (i.e., crystal data, permittivity, impedance, electrical cobnduction and magnetic) of a multiferroic material with a chemical composition (SmLi)1/2(Fe2/3Mo1/3)O3 have been reported. Thermogravimetric analysis of the compound, prepared by cost effective ceramic technology processing, was executed to check the mass loss as well as the required decomposition temperature of the ingredients. An analysis of X-ray spectra or pattern suggests that the crystallization phase or cystal system of the compound at room temperature is orthorhombic. The broad studies of dielectric properties {relative dielectric constant (εr), and tangent loss (tan δ)} display their independence of temperature and frequency in the rage of (30-375 °C) and (1 kHz-1 MHz) respectively. The impedance spectroscopic technique has provided a considerable significant information regarding the grain, grain boundary contribution within the sample and relaxation mechanism of the compound. The occurrence of negative temperature coefficient behaviour (NTCR) is depicted by the further analysis of impedance parameters. The frequency-temperature dependence of conductivity follows the Johnson’s power Universal law. The Arrhenius plot (i.e., variation of electrical conductivity with temperature) is used to calculate the activation energy. Analysis of magnetization (M-H) loop shows weak ferromagnetism of the compound. The material possesses significantly high magnitude of magnetoelectric coefficient of 3.0 mV Cm− 1 Oe− 1. [ABSTRACT FROM AUTHOR]

Building upon our earlier studies of cobaltaheteroboranes, we explore the chemistry with heavier group 9 metals. Reaction of [Cp*M(µ‐Cl)Clx]2 (Cp* = η5‐C5Me5; M = Co, x = 0; M = Rh or Ir, x = 1) with [LiBH4·THF], followed by thermolysis with an excess of chalcogen powders (S or Se), affords dimetallaheteroboranes nido‐[(Cp*M)2B2H2E2], 1–4 (1: E = S; 2: E = Se, M = Co; 3 and 4: E = Se, M = Rh and Ir, respectively) in moderate‐to‐good yields. The solid‐state structures of these compounds show open‐cage triple‐decker clusters. Attempts to isolate the Te analogue have failed; however, in the case of cobalt, we have isolated an 11 skeletal‐electron‐pair nido‐[(Cp*Co)2B5H5Te2], 5. The X‐ray diffraction structure of 5 shows monocapped square antiprismatic geometry, with two Te atoms in the core. To close the central four‐membered B2E2 open ring of nido‐1 and nido‐2, we have performed a reaction with [Ru3(CO)12], which leads to the formation of closo‐[(Cp*Co){µ‐η5:η5‐B2H2E2M}M{µ‐Ru(CO)4}], 6 and 7 [6: E = S; 7: E = Se; M = Ru(CO)2]. In contrast, the reactions of nido‐2 and nido‐3 with [Fe2(CO)9] result in heterometallic clusters nido‐[(Cp*M)Fe(CO)3B2H2Se2], 8 and 9 (8: M = Co; 9: M = Rh), [(Cp*Co)Fe3(CO)8Se2], 10, and [(Cp*Co)Fe2(CO)7Se], 11. As nido‐8 also contains a four‐membered open ring B2Se2, we have treated this with [Ru3(CO)12], which yields closo‐[(Cp*Co){µ‐η5:η5‐B2H2Se2M}M{µ‐Fe(CO)4}], 12 [M = Ru(CO)2], which is analogous to that of 7. In addition, we have analyzed the divergence in the reactivity of nido‐[(Cp*M)2B2H2E2], 2–4, with the help of density functional theory calculations. [ABSTRACT FROM AUTHOR]

The syntheses and structural characterization of the CS2-metal complexes [(η5-C5Me5M)(η2-S2CH2)(η3-S2CH)] ( 1: M = Mo; 2: M = W), which feature partially and fully reduced CS2, are reported. In addition, the cis and trans isomers of the dimetallic (sulfido)molybdenum complexes [(η5-C5Me5Mo)2(µ-S2CH2S)2] ( 3- cis and 4- trans) are described. The [Mo2S4] cores of 3- cis and 4- trans represent paddlewheel-like arrays. All the new compounds were characterized in solution by mass spectrometry, IR spectroscopy, and 1H and 13C NMR spectroscopy. Their structural architectures were established by X-ray crystallographic analysis. Quantum-chemical calculations by DFT methods on the model compounds 1′- 4′- trans showed good agreement with the experimentally observed structural parameters. The large HOMO-LUMO (HOMO = highest occupied molecular orbital, LUMO = lowest unoccupied molecular orbital) gaps are consistent with the high thermodynamic stabilities of these complexes. Further, the presence of short metal-metal cross-cluster bonds in the X-ray structures of 3- cis and 4- trans is supported by natural bond order (NBO) calculations. [ABSTRACT FROM AUTHOR]

Reaction of [(η5-C5Me5)CoCl]2 with a two-fold excess of [LiBH4·thf] followed by heating with an excess of Se powder produces the dicobaltaselenaborane species [{(η5-C5Me5)Co}2B2H2Se2], 1, in good yield. The geometry of 1 resembles a nido pentagonal [Co2B2Se2] bipyramid with a missing equatorial vertex. It can alternatively be seen as an open cage triple-decker cluster. Isolation of 1 permits its reaction with [Fe2(CO)9] to give heterometallic diselenametallaborane [{(η5-C5Me5)Co}Fe(CO)3B2H2Se2], 2. The geometry of 2 is similar to that of 1 with one of the [(η5-C5Me5)Co] groups replaced by the isolobal, two-electron fragment [Fe(CO)3]. Both new compounds have been characterized by mass spectrometry, and by 1H, 11B and 13C NMR spectroscopy. The structural architectures have been unequivocally established by crystallographic analysis. In addition, density functional theory calculations were performed to investigate the bonding and electronic properties. The large HOMO–LUMO gaps computed for both clusters are consistent with their thermodynamic stability. Natural bond order calculations predict the absence of metal–metal bonding interaction. [ABSTRACT FROM AUTHOR]

Theregioselective 1,3-dipolar cycloaddition reaction of alkoxyalkynyl Fischer carbene complex 1with azidomethyl ferrocene 2and with azidomethyl pyrene 4under solvent-freeconditions yielded the triazolyl Fischer carbene complexes 3(C27H21O6N3FeW) and 5(C33H21O6N3W),respectively. The cation complexation properties of these receptorshave been systematically studied using electrochemical and spectroscopictechniques. The exceptional structural feature existing in these receptorsis the presence of a Fischer carbene moiety, connected to the ferroceneor pyrene moiety through a 1,2,3-triazole ring. Receptor 3contains a redox-active ferrocene moiety and is highly selectivetoward Pb2+ion, whereas receptor 5, havinga fluorescent pyrene unit, selectively recognizes Zn2+andCu2+ions. The binding ability of receptor 3can be inferred either from the redox shift (the anodic shift ΔE1/2= 55 mV) or the highly visual output responsefor Pb2+ion. Receptor 5displays considerablechelation-enhanced fluorescence (CHEF) upon binding with Zn2+and Cu2+ions in an aqueous environment. Further, theproposed binding modes of these receptors and their metal cation complexationproperties have been supported by 1H NMR titration andMALDI-MS and a DFT study. [ABSTRACT FROM AUTHOR]

The synthesis, structural characterization, and reactivity of new bridged borylene complexes are reported. The reaction of [{Cp*CoCl}2] with LiBH4 ⋅THF at −70 °C, followed by treatment with [M(CO)3(MeCN)3] (M=W, Mo, and Cr) under mild conditions, yielded heteronuclear triply bridged borylene complexes, [(μ3-BH)(Cp*Co)2(μ-CO)M(CO)5] ( 1- 3; 1: M=W, 2: M=Mo, 3: M=Cr). During the syntheses of complexes 1- 3, capped-octahedral cluster [(Cp*Co)2(μ-H)(BH)4{Co(CO)2}] ( 4) was also isolated in good yield. Complexes 1- 3 are isoelectronic and isostructural to [(μ3-BH)(Cp*RuCO)2(μ-CO){Fe(CO)3}] ( 5) and [(μ3-BH)(Cp*RuCO)2(μ-H)(μ-CO){Mn(CO)3}] ( 6), with a trigonal-pyramidal geometry in which the μ3-BH ligand occupies the apical vertex. To test the reactivity of these borylene complexes towards bis-phosphine ligands, the room-temperature photolysis of complexes 1- 3, 5, 6, and [{(μ3-BH)(Cp*Ru)Fe(CO)3}2(μ-CO)] ( 7) was carried out. Most of these complexes led to decomposition, although photolysis of complex 7 with [Ph2P(CH2) nPPh2] ( n=1-3) yielded complexes 9- 11, [3,4-(Ph2P(CH2) nPPh2)- closo-1,2,3,4-Ru2Fe2(BH)2] ( 9: n=1, 10: n=2, 11: n=3). Quantum-chemical calculations by using DFT methods were carried out on compounds 1- 3 and 9- 11 and showed reasonable agreement with the experimentally obtained structural parameters, that is, large HOMO-LUMO gaps, in accordance with the high stabilities of these complexes, and NMR chemical shifts that accurately reflected the experimentally observed resonances. All of the new compounds were characterized in solution by using mass spectrometry, IR spectroscopy, and 1H, 13C, and 11B NMR spectroscopy and their structural types were unequivocally established by crystallographic analysis of complexes 1, 2, 4, 9, and 10. [ABSTRACT FROM AUTHOR]

The preparation, characterization, and electronic structure of the first heterometallic μ9-boride cluster [(Cp*Rh)2{Co6(CO)I2}(μ-H)(BH)B)] has been reported. The interstitial boron atom in the title cluster is within the bonding contact of eight metal and one boron atom in a unique tricapped trigonal prism geometry. [ABSTRACT FROM AUTHOR]

The bulk ceramics bearing chemical formula BiFeO3 and (BiLi)1/2(Fe2/3Mo1/3)O3 (abbreviated as BFO and BLFMO respectively) are synthesized using mixed oxide route. The physical properties (structural, dielectric, electric and magnetic) are tailored in Li and Mo co-doped BiFeO3. The phase evolution suggests that there is transformation from rhombohedral (pure BFO) to orthorhombic (BLFMO). Micro-structural suggests that due to co-doping the size of the grain is smaller than BFO. The dielectric properties of both BFO and BLFMO measure with an LCR meter varying the frequency (102–106 Hz) and temperature (30–375 °C). The leakage current decreases in BLFMO. The magnetic hysteresis loop owing weak ferromagnetism is depicted for Li and Mo co-doped BFO. The fabricated material will be base for various applications like filter and buffering. [ABSTRACT FROM AUTHOR]

The bulk ceramics bearing chemical formula BiFeO3 and (BiLi)1/2(Fe2/3Mo1/3)O3 (abbreviated as BFO and BLFMO respectively) are synthesized using mixed oxide route. The physical properties (structural, dielectric, electric and magnetic) are tailored in Li and Mo co-doped BiFeO3. The phase evolution suggests that there is transformation from rhombohedral (pure BFO) to orthorhombic (BLFMO). Micro-structural suggests that due to co-doping the size of the grain is smaller than BFO. The dielectric properties of both BFO and BLFMO measure with an LCR meter varying the frequency (102–106 Hz) and temperature (30–375 °C). The leakage current decreases in BLFMO. The magnetic hysteresis loop owing weak ferromagnetism is depicted for Li and Mo co-doped BFO. The fabricated material will be base for various applications like filter and buffering. [ABSTRACT FROM AUTHOR]

A new polycrystalline ceramic sample of (Sb1/2Na1/2)(Fe2/3Mo1/3)O3 is formed by cheap mixed oxide processing technique. The mass loss and the calcination temperature of the sample are optimized by thermogravimetric analysis and repeated firing. The formed sample crystallizes in the orthorhombic crystal structure at room temperature depicted from the X-ray diffraction spectra. The dielectric relaxation, impedance and modulus analysis of the sample have been analyzed in various temperature and frequency range. The dielectric parameters of the sample depend on frequency and temperature and with an increment in temperature the relaxation time falls. Impedance spectroscopy analysis predicts the association of grain and grain boundary resistance. The short and long-range mobility of the charge carriers are illustrated by the modulus plot. Ac conductivity is seen to be temperature and frequency dependent and hopping of the charge carriers is also observed at high temperature. Further, the universal power law is followed by ac conductivity mechanism. [ABSTRACT FROM AUTHOR]